Summary
In the full sample, we saw a marginal effect of shape: right handers’
vs. left handers’ LVF global bias is 15.89ms greater for square targets
than for circles (95% CI [-5.99, 37.76], p = .08, one-sided). We also
saw that the estimated LVF global bias difference was greater between
strong right and left handers (EHI +/- 100: 23.51ms difference) than
between the default handedness groups (EHI </> +-40: 11.67ms
difference).
When we limit analysis to squares only and EHI extremes,
strong left handers have a further reduced (very close to zero), but not
reversed, LVF global bias.
Strong left handers’ estimated LVF global bias for squares (2.45ms,
95%CI [-15.18, 20.01]) is lower than for circles (7.20ms, 95%CI [-9.98,
24.37]), but this difference is not significant (-4.74ms, 95%CI [-29.10,
19.62], p = .35, one-sided). With squares and circles combined, strong
left handers’ LVF global bias was 4.59ms (95%CI [-7.90, 16.98]).
The critical three-way interaction effect is stronger in this
analysis of squares only and EHI extremes (34.68ms, 95%CI [11.35,
58.01], p = .002, one-sided). The three-way effect for the full sample
with both shapes was 11.67ms (95%CI [0.65, 22.69], p = .019, one-sided),
for the full sample with squares only it was 19.76ms (95%CI [4.11,
35.40], p = .006, one-sided), and for EHI extremes with both shapes it
was 23.51ms (95% CI [7.10, 39.92], p = .0025, one-sided).
Analyses
Field by level by shape
Does the interaction of field by level differ depending on shape
(square vs. circle), for extreme left and right handers (EHI +/-
100)?
Reaction time is modeled as a linear effect of field, level, and
handedness, using data from every target-present trial with a “go”
response:
lmer( rt ~ field*level*shape + (1 | subject) )
Extreme righties (EHI +100; n = 182)
| N |
Age (years) |
Education (years) |
Sex (M/F/O) |
EHI |
| 182 |
29.87 (6.14) |
14.34 (2.48) |
96/85/1 |
100 (0) |
| npar |
AIC |
BIC |
logLik |
deviance |
Chisq |
Df |
p.value |
| 9 |
300,066.118 |
300,138.19 |
−150,024.059 |
300,048.118 |
- |
- |
- |
| 10 |
300,065.772 |
300,145.851 |
−150,022.886 |
300,045.772 |
2.346 |
1 |
.126 |
| field_consec |
level_consec |
shape_consec |
estimate |
SE |
df |
asymp.LCL |
asymp.UCL |
z.ratio |
p.value |
| LVF - RVF |
Local - Global |
Square - Circle |
16.819 |
10.981 |
Inf |
−4.704 |
38.341 |
1.532 |
.126 |
| field_consec |
level_consec |
shape |
estimate |
SE |
df |
asymp.LCL |
asymp.UCL |
z.ratio |
p.value |
| LVF - RVF |
Local - Global |
Circle |
20.314 |
7.675 |
Inf |
5.272 |
35.357 |
2.647 |
.008 |
| LVF - RVF |
Local - Global |
Square |
37.133 |
7.854 |
Inf |
21.74 |
52.526 |
4.728 |
<.0001 |
| contrast |
estimate |
SE |
df |
asymp.LCL |
asymp.UCL |
z.ratio |
p.value |
| RVF Local Circle - RVF Global Circle |
−6.596 |
5.44 |
Inf |
−17.257 |
4.065 |
−1.213 |
.225 |
| LVF Local Circle - LVF Global Circle |
13.718 |
5.415 |
Inf |
3.105 |
24.332 |
2.533 |
.011 |
| RVF Local Square - RVF Global Square |
19.649 |
5.565 |
Inf |
8.743 |
30.555 |
3.531 |
.0004 |
| LVF Local Square - LVF Global Square |
56.782 |
5.547 |
Inf |
45.91 |
67.654 |
10.236 |
<.0001 |
| field |
level |
shape |
emmean |
SE |
df |
asymp.LCL |
asymp.UCL |
| LVF |
Global |
Circle |
670.484 |
12.95 |
Inf |
645.103 |
695.865 |
| LVF |
Local |
Circle |
684.203 |
12.954 |
Inf |
658.814 |
709.592 |
| LVF |
Global |
Square |
703.021 |
12.958 |
Inf |
677.624 |
728.419 |
| LVF |
Local |
Square |
759.803 |
13.001 |
Inf |
734.321 |
785.285 |
| RVF |
Global |
Circle |
685.713 |
12.958 |
Inf |
660.317 |
711.11 |
| RVF |
Local |
Circle |
679.117 |
12.956 |
Inf |
653.724 |
704.511 |
| RVF |
Global |
Square |
717.007 |
12.972 |
Inf |
691.583 |
742.431 |
| RVF |
Local |
Square |
736.656 |
12.995 |
Inf |
711.186 |
762.127 |
Extreme lefties (EHI -100; n = 182)
| N |
Age (years) |
Education (years) |
Sex (M/F/O) |
EHI |
| 138 |
30.07 (5.87) |
14.68 (2.45) |
81/56/1 |
-100 (0) |
| npar |
AIC |
BIC |
logLik |
deviance |
Chisq |
Df |
p.value |
| 9 |
225,667.688 |
225,737.218 |
−112,824.844 |
225,649.688 |
- |
- |
- |
| 10 |
225,669.542 |
225,746.798 |
−112,824.771 |
225,649.542 |
0.146 |
1 |
.703 |
| field_consec |
level_consec |
shape_consec |
estimate |
SE |
df |
asymp.LCL |
asymp.UCL |
z.ratio |
p.value |
| LVF - RVF |
Local - Global |
Square - Circle |
−4.744 |
12.429 |
Inf |
−29.103 |
19.616 |
−0.382 |
.703 |
| field_consec |
level_consec |
shape |
estimate |
SE |
df |
asymp.LCL |
asymp.UCL |
z.ratio |
p.value |
| LVF - RVF |
Local - Global |
Circle |
7.197 |
8.672 |
Inf |
−9.799 |
24.193 |
0.83 |
.407 |
| LVF - RVF |
Local - Global |
Square |
2.454 |
8.904 |
Inf |
−14.997 |
19.905 |
0.276 |
.783 |
| contrast |
estimate |
SE |
df |
asymp.LCL |
asymp.UCL |
z.ratio |
p.value |
| RVF Local Circle - RVF Global Circle |
3.914 |
6.137 |
Inf |
−8.114 |
15.942 |
0.638 |
.524 |
| LVF Local Circle - LVF Global Circle |
11.111 |
6.129 |
Inf |
−0.901 |
23.123 |
1.813 |
.07 |
| RVF Local Square - RVF Global Square |
37.616 |
6.312 |
Inf |
25.244 |
49.988 |
5.959 |
<.0001 |
| LVF Local Square - LVF Global Square |
40.07 |
6.29 |
Inf |
27.742 |
52.398 |
6.371 |
<.0001 |
| field |
level |
shape |
emmean |
SE |
df |
asymp.LCL |
asymp.UCL |
| LVF |
Global |
Circle |
623.203 |
15.518 |
Inf |
592.788 |
653.618 |
| LVF |
Local |
Circle |
634.314 |
15.524 |
Inf |
603.888 |
664.74 |
| LVF |
Global |
Square |
656.067 |
15.526 |
Inf |
625.637 |
686.497 |
| LVF |
Local |
Square |
696.137 |
15.581 |
Inf |
665.599 |
726.675 |
| RVF |
Global |
Circle |
649.546 |
15.523 |
Inf |
619.122 |
679.97 |
| RVF |
Local |
Circle |
653.46 |
15.523 |
Inf |
623.035 |
683.884 |
| RVF |
Global |
Square |
675.247 |
15.541 |
Inf |
644.788 |
705.706 |
| RVF |
Local |
Square |
712.863 |
15.575 |
Inf |
682.337 |
743.39 |
Field by level by handedness by
shape
Does the interaction of field by level by handedness differ depending
on shape (square vs. circle), for extreme left and right handers (EHI
+/- 100)?
Reaction time is modeled as a linear effect of field, level,
handedness (EHI < -100 or EHI > +100), and shape, using data from
every target-present trial with a “go” response:
lmer( rt ~ field * level * handedness * shape + (1 | subject) )
| Handedness |
N |
Age (years) |
Education (years) |
Sex (M/F/O) |
EHI |
| Left |
138 |
30.07 (5.87) |
14.68 (2.45) |
81/56/1 |
-100 (0) |
| Right |
182 |
29.87 (6.14) |
14.34 (2.48) |
96/85/1 |
100 (0) |
| npar |
AIC |
BIC |
logLik |
deviance |
Chisq |
Df |
p.value |
| 17 |
525,737.216 |
525,882.904 |
−262,851.608 |
525,703.216 |
- |
- |
- |
| 18 |
525,737.534 |
525,891.791 |
−262,850.767 |
525,701.534 |
1.682 |
1 |
.195 |
| field_consec |
level_consec |
handedness_consec |
shape_consec |
estimate |
SE |
df |
asymp.LCL |
asymp.UCL |
z.ratio |
p.value |
| LVF - RVF |
Local - Global |
Right - Left |
Square - Circle |
21.562 |
16.626 |
Inf |
−11.024 |
54.147 |
1.297 |
.195 |
| field_consec |
level_consec |
handedness_consec |
shape |
estimate |
SE |
df |
asymp.LCL |
asymp.UCL |
z.ratio |
p.value |
| LVF - RVF |
Local - Global |
Right - Left |
Circle |
13.118 |
11.609 |
Inf |
−9.635 |
35.87 |
1.13 |
.258 |
| LVF - RVF |
Local - Global |
Right - Left |
Square |
34.68 |
11.902 |
Inf |
11.352 |
58.008 |
2.914 |
.004 |
| field_consec |
level_consec |
shape_consec |
handedness |
estimate |
SE |
df |
asymp.LCL |
asymp.UCL |
z.ratio |
p.value |
| LVF - RVF |
Local - Global |
Square - Circle |
Left |
−4.743 |
12.555 |
Inf |
−29.35 |
19.864 |
−0.378 |
.706 |
| LVF - RVF |
Local - Global |
Square - Circle |
Right |
16.818 |
10.899 |
Inf |
−4.544 |
38.18 |
1.543 |
.123 |
| field_consec |
level_consec |
handedness |
shape |
estimate |
SE |
df |
asymp.LCL |
asymp.UCL |
z.ratio |
p.value |
| LVF - RVF |
Local - Global |
Left |
Circle |
7.197 |
8.76 |
Inf |
−9.972 |
24.366 |
0.822 |
.411 |
| LVF - RVF |
Local - Global |
Right |
Circle |
20.315 |
7.618 |
Inf |
5.385 |
35.245 |
2.667 |
.008 |
| LVF - RVF |
Local - Global |
Left |
Square |
2.454 |
8.994 |
Inf |
−15.175 |
20.082 |
0.273 |
.785 |
| LVF - RVF |
Local - Global |
Right |
Square |
37.133 |
7.795 |
Inf |
21.855 |
52.412 |
4.764 |
<.0001 |
Plots
Error bars show 95% CI. Left handers are those with EHI = -100; Right
handers, EHI = +100.


